Sherlock Holmes and the Missing Bronte

It was Dr Watson who spotted the ad in the Times when he was using it to light the fire:

'Consulting detective urgently required. The Rev Brontë will be in attendance at the Old Chapter Coffee House, Paternoster Square until the 17th inst.

The reverend gentleman's son Branwell had been in the employ of Rorke's Drift hero, Lord Broomhead, as tutor to his son Miles. He's gone missing, as has the Star of Life, a priceless gem and most treasured possession of Ayesha, Broomhead's wife. Rev Brontë wants Holmes to find the gem and, more importantly, clear his son's name. . .